const cp = require('child_process')
const {
  resolve
} = require('path')

;
(async () => {
  const script = resolve(__dirname, '../crawler/preview-list')

  const child = cp.fork(script, [])
  let invoked = false
  child.on('error', err => {
    if (invoked) return
    invoked = true
    console.log(err);
  })
  child.on('exit', code => {
    if (invoked) return
    invoked = true
    let err = code === 0 ? null : new Error('exit code' + code)
    console.log(err);
  })
  child.on('message', data => {
    let result = data.result
    console.log(result);
  })
})()